Rats in a new study out of Arizona State University were given the green light, or rather, they got a dose from green LEDs, or light-emitting diodes, in research that tested whether the light treatment could alleviate chronic pain. Results showed the rodents were able to withstand more heat and touch after the treatment, though researchers don’t know if people would similarly benefit.

Following their success with rats, researchers are now testing a small group of people with pain from fibromyalgia to see how they respond to the green LED therapy. The participants will sit in a dark room lit only by a green LED strip for a couple of hours each night for 10 weeks, a press release from ASU reported.

“While the pain-relieving qualities of green LED are clear, exactly how it works remains a puzzle,” said senior study author Rejesh Khanna, according to the release.

Light therapy is a treatment in which you’re exposed to an artificial light source, Healthline reported, and it’s also known as phototherapy. We’ve listed some other health problems that may also benefit from light therapy, according to scientific studies.

Low Testosterone

Back in September 2016, researchers from the University of Siena in Italy examined the effect of light therapy on men suffering from clinically low libido. In the study, they exposed a group of participants to light that mimicked natural outdoor sunlight. Results showed the light therapy group had higher amounts of testosterone in their blood and a substantial increase in sexual desire and function, Medical Daily reported at the time.

Seasonal Affective Disorder

Light therapy is a way to treat seasonal affective disorder (SAD) — which typically occurs in fall or winter. Bright, sun-like light has been shown to ease the symptoms of this anxiety disorder, The Mayo Clinic reported.